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PHENYLKETONURIA A CASE STUDY

LYDIA Y

Abstract


Classical type of phenylketonuria (PKU) is characterized by complete or near complete deficiency of phenylalanine hydroxylase. Classical PKU is associated with less than 2 activity of normal phenylalanine hydroxylase. The infants are normal at birth, if the disease is unrecognized and untreated, mental retardation may develop gradually and may not be evident for few months. Symptoms of PKU can range from mild to severe. The most severe form of this disorder is known as classic PKU. An infant with classic PKU may appear normal for the first few months of his or her life. If the child is not treated for PKU during this time, he or she will begin to develop symptoms such as intellectual disabilities or mental retardation, seizures tremors or jerky hand and leg movements,  hyperactivity. stunted growth, eczema, distinct odor in breath, skin that is often described as mousy odour, lighter skin, hair, and eye color than their family members. . A mousy odour in the child's breath, skin caused by too much phenylalanine in the body. Fair skin and blue eyes are present because                     phenylalanine cannot be transformed into melanin, the pigment responsible for hair and skin tone. Abnormally small head (microcephaly) can also be present. A less severe form of this disorder is called variant PKU or non-PKU                                 hyperphenylalaninemia (having too much phenylalanine.)              Children with this form of the disorder may have only mild  symptoms, but they will need to follow a special diet to prevent mental retardation. In rare cases in which the disorder was not diagnosed at birth and treatment was not started quickly,           symptoms of PKU can cause irreversible brain damage and mental retardation within the first few months of life, behavioural problems and seizures in older children Once a specific diet and other necessary treatments are started, symptoms diminish. People with PKU who properly manage their diet dont show any symptoms.

 


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